BNC: Body – Brass, Tarnish Resistant Plating Center Contact – Gold Plated Beryllium Copper Insulation: Teflon per ASTM-D-1457 Finish: Body and Fittings – Tarnish resistant, Center Contact – Gold Plated P.C. Pins: Silver Plated Marking: ¡°POMONA 4578¡± located approximately as shown